in order to bounce this EUV light down on to the wafer, ASML has contracted Zeiss to produce a set of special mirrors called Bragg reflectors, made from layers of silicon and molybdenum. Quite how these mirrors are made is yet another closely guarded trade secret, but according to Zeiss, they are ground down from blocks weighing 50 kilograms, and robots are used to polish and correct the outer layer with ion beams. Suffice it to say, they are, according to one ASML engineer, “probably the smoothest man-made structures in the universe.” If you blew one of them up to the size of the United
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